#1814 · Probability · Conditional probability
Drawing red balls from a bag
A bag contains 5 balls of unknown colour; a ball is drawn and replaced twice, and in each case is found to be red: if two balls are now drawn simultaneously find the chance that both are red.
H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XXXII. Probability, Examples XXXII.d, No. 7
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Checked against the answer in H. S. Hall & S. R. Knight, Higher Algebra (1891).